If the motor turns on, it shouldn't need rebuilding, or even really repaired. There's a couple things you can check yourself before you go through the hassle of dismounting the motor and taking it to a shop. First, try a different outlet. It could be that there's something wrong with the present outlet that's keeping the motor from getting all the power that it needs. Secondly, take the belt off and try spinning the motor armeture by hand. It should be nice and smooth, if it feels gritty or has a hitch somewhere, it needs new bearings. That's a simple job, no need to take it to a shop if you own a screwdriver. Now try powering the motor without the belt. It should get up to speed pretty well, and you should hear a 'click' sound. If you don't hear that click, the starter winding switch isn't disengaging and that's why the motor doesn't seem to have enough power. Fixing that, unfortunately, is a job for a repair shop.
Since the motor runs, its not very likely that you have a dead capacitor or damaged windings, so its probably something simple. I should also not, this advise all assumes your bandsaw is properly set up. If, say, the blade guides are mis-aligned and pinching the blade, the motor won't have enough starting torque to get everything moving, so check the basic setup too